Lyonisation of human aberrant, x-chromosome with deletion of short arm [del (x) (p11)]

A female with secondary amenorrhoea was found to have a complete deletion of the short arm of chromosome X (Xp-) with almost no features of Turner's syndrome. The replication profile on Xq was further evaluated and was found to be compatible with normal Xq using eight normal females as controls. Only G-negative bands were early replicating. The highest incidence of early replicating bands was noted for band q13. It is suggested that q13, q24 and q28 could be critical bands in sexual development, due to the presence of some similarity of replicating pattern.